Apparatus and method for replacing a diseased cardiac valve

ABSTRACT

An apparatus for replacing a diseased cardiac valve is movable from a radially collapsed configuration to a radially expanded configuration. The apparatus comprises an expandable support member and a prosthetic valve secured therein. The main body portion extends between first and second end portions and includes an outer circumferential surface, a circumferential axis extending about the circumferential surface, and a plurality of wing members spaced apart from one another by an expandable region. Each of the wing members includes first and second end portions and a flexible middle portion extending between the end portions. The second end portion is integrally formed with the uyimain body portion. The first end portion is adjacent the circumferential axis and substantially flush with the outer circumferential surface in the radially collapsed configuration. The first end portion extends substantially radial to the outer circumferential surface in the radially expanded configuration.

RELATED APPLICATIONS

This application claims priority from U.S. patent application Ser. No.12/828,991 filed Jul. 1, 2010, issued as U.S. Pat. No. 8,685,086 on Apr.1, 2014, which is a continuation in part of patent application Ser. No.11/357,485 filed Feb. 18, 2006 and a continuation in part of patentapplication Ser. No. 12/769,593 filed Apr. 28, 2010, and provisionalpatent application Ser. No. 61/222,518, filed on Jul. 2, 2009, thesubject matter of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates generally to cardiac valve repair andreplacement, and more particularly to an apparatus and method for thecorrection of cardiac valve disorders.

BACKGROUND OF THE INVENTION

Diseased mitral and tricuspid valves frequently need replacement orrepair. The mitral and tricuspid valve leaflets or supporting chordaemay degenerate and weaken or the annulus may dilate leading to valveleak (i.e., valve insufficiency). The leaflets and chords may becomecalcified and thickened, rendering them stenotic and obstructing forwardblood flow. Finally, each of the valves relies on insertion of thechordae inside the ventricle. If the corresponding ventricle changesshape, the valve support may become non-functional and the valve mayleak.

Mitral and tricuspid valve replacement and repair are traditionallyperformed with a suture technique. During valve replacement, sutures arespaced around the annulus and then attached to a prosthetic valve. Thevalve is lowered into position and, when the sutures are tied, the valveis fastened to the annulus. The surgeon may remove all or part of thevalve leaflets before inserting the prosthetic valve.

In valve repair, a diseased valve is left in situ and surgicalprocedures are performed to restore its function. Frequently, anannuloplasty ring is used to reduce the size of the annulus. The ringserves to reduce the diameter of the annulus and allow the leaflets tooppose each other normally. Sutures are used to attach a prosthetic ringto the annulus and to assist in plicating the annulus.

In general, the annuloplasty rings and replacement valves must besutured to the valve annulus during a time consuming and tediousprocedure. If the ring is severely malpositioned, then the stitches mustbe removed and the ring repositioned relative to the valve annulus. Inother cases, a less than optimum annuloplasty may be tolerated by thesurgeon rather than lengthening the time of the surgery to re-stitch thering. Moreover, during heart surgery, a premium is placed on reducingthe amount of time used to replace and repair valves as the heart isfrequently arrested and without perfusion.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, an apparatus forreplacing a diseased cardiac valve comprises an expandable supportmember and a prosthetic valve secured within a main body portion of theexpandable support member. The apparatus is movable from a radiallycollapsed configuration to a radially expanded configuration. Theexpandable support member has a first end portion and a second endportion. The main body portion extends between the first and second endportions. The main body portion also includes an outer circumferentialsurface, a circumferential axis extending about the outercircumferential surface, and a plurality of wing members spaced apartfrom one another by an expandable region. Each of the wing membersincludes a first end portion, a second end portion, and a flexiblemiddle portion extending between the first and second end portions. Thesecond end portion of each of the wing members is integrally formed withthe main body portion. The first end portion of each of the wing membersis adjacent the circumferential axis and substantially flush with theouter circumferential surface when the apparatus is in the radiallycollapsed configuration. The first end portion of each of the wingmembers extends substantially radial to the outer circumferentialsurface when the apparatus is in the radially expanded configuration.

According to another aspect of the present invention, a method isprovided for replacing a diseased cardiac valve. One step of the methodincludes providing an apparatus comprising an expandable support memberhaving a prosthetic valve secured within a main body portion of theexpandable support member. The main body portion also includes an outercircumferential surface, a circumferential axis extending about theouter circumferential surface, and a plurality of wing members spacedapart from one another by an expandable region. Each of the wing membersincludes a first end portion, a second end portion, and a flexiblemiddle portion extending between the first and second end portions. Thesecond end portion of each of the wing members is integrally formed withthe main body portion. The expandable support member is placed, in aradially collapsed configuration, about an inflatable member and thenloaded into a delivery catheter. Next, the delivery catheter is advancedto the diseased cardiac valve. The apparatus is then deployed, in aradially expanded configuration, so that the first end portion of eachof the wing members extends substantially radial to the outercircumferential surface. Deployment of the apparatus causes the firstend portion of each of the wing members to contact cardiac tissue andthereby secure the apparatus in place of the diseased cardiac valve.

According to another aspect of the present invention, a method isprovided for replacing a diseased cardiac valve. One step of the methodincludes providing an apparatus comprising an expandable support memberhaving a prosthetic valve secured within a main body portion of theexpandable support member. The main body portion also includes an outercircumferential surface, a circumferential axis extending about theouter circumferential surface, and a plurality of wing members spacedapart from one another by an expandable region. Each of the wing membersincludes a first end portion, a second end portion, and a flexiblemiddle portion extending between the first and second end portions. Thesecond end portion of each of the wing members is integrally formed withthe main body portion. The expandable support member is placed in aradially collapsed configuration and then advanced to the diseasedcardiac valve. The apparatus is then deployed, in a radially expandedconfiguration, so that the first end portion of each of the wing membersextends substantially radial to the outer circumferential surface.Deployment of the apparatus causes the first end portion of each of thewing members to contact cardiac tissue and thereby secure the apparatusin place of the diseased cardiac valve.

According to another aspect of the present invention, an apparatus forreplacing an indwelling bioprosthetic valve has at least two commissuralportions spaced apart by a first distance. The apparatus is movable froma radially collapsed configuration to a radially expanded configuration.The apparatus comprises an expandable support member having a first endportion, a second end portion, and a main body portion extending betweenthe first and second end portions. The main body portion includes anouter circumferential surface and a circumferential axis extending aboutsaid outer circumferential surface. The apparatus also comprises aprosthetic valve secured within the main body portion of the expandablesupport member. The second end portion includes at least two flexiblearch members spaced apart by a second distance that is about equal tothe first distance. Each of the at least two arch members issubstantially co-planar with the outer circumferential surface when theapparatus is in the radially collapsed configuration, and substantiallyradial to the outer circumferential surface when the apparatus is in theradially expanded configuration. The main body portion includes aplurality of wing members spaced apart from one another by an expandableregion. Each of the wing members includes a first end portion, a secondend portion, and a flexible middle portion extending between the firstand second end portions. The second end portion of each of the wingmembers is integrally formed with the main body portion. The first endportion of each of the wing members is adjacent the circumferential axisand substantially flush with the outer circumferential surface when theapparatus is in the radially collapsed configuration. The first endportion of each of the wing members extends substantially radial to theouter circumferential surface when the apparatus is in the radiallyexpanded configuration.

According to another aspect of the present invention, a method isprovided for replacing an indwelling bioprosthetic valve in a subject.The indwelling bioprosthetic valve has at least two commissural portionsspaced apart by a first distance. One step of the method includesproviding an apparatus comprising an expandable support member and aprosthetic valve secured within a main body portion of the expandablesupport member. The main body portion includes an outer circumferentialsurface, a circumferential axis extending about the circumferentialsurface, and a plurality of wing members spaced apart from one anotherby an expandable region. Each of the wing members includes a first endportion, a second end portion, and a flexible middle portion extendingbetween the first and second end portions. The second end portion ofeach of the wing members is integrally formed with the main bodyportion. The apparatus is loaded into a delivery catheter and thenadvancing the delivery catheter to the indwelling bioprosthetic valve.Next, the apparatus is deployed, in a radially expanded configuration,so that each of the at least two arch members engages each of the atleast two commissural portions and the first end portion of each of thewing members extends substantially radial to the outer circumferentialsurface to displace a valve portion of the indwelling bioprostheticvalve.

According to another aspect of the present invention, an apparatus forreplacing an indwelling bioprosthetic valve has at least two commissuralportions spaced apart by a first distance. The apparatus is movable froma radially collapsed configuration to a radially expanded configuration.The apparatus comprises a cork-shaped expandable support member having afirst end portion, a second end portion, and a main body portionextending between the first and second end portions. The first endportion has a flared configuration and includes a diameter that isgreater than a diameter of the second end portion. The main body portionincludes an outer circumferential surface and a circumferential axisextending about said outer circumferential surface. The apparatus alsocomprises a prosthetic valve secured within the first end portion of theexpandable support member. The main body portion includes a plurality ofwing members spaced apart from one another by an expandable region. Eachof the wing members includes a first end portion, a second end portion,and a flexible middle portion extending between the first and second endportions. The second end portion of each of the wing members isintegrally formed with the main body portion. The first end portion ofeach of the wing members is adjacent the circumferential axis andsubstantially flush with the outer circumferential surface when theapparatus is in the radially collapsed configuration. The first endportion of each of the wing members extends substantially radial to theouter circumferential surface when the apparatus is in the radiallyexpanded configuration.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features of the present invention will becomeapparent to those skilled in the art to which the present inventionrelates upon reading the following description with reference to theaccompanying drawings, in which:

FIG. 1A is a perspective view showing an apparatus for replacing adiseased cardiac valve, in a radially collapsed configuration,constructed in accordance with one aspect of the present invention;

FIG. 1B is the apparatus in FIG. 1A in a radially expandedconfiguration;

FIG. 2 is a view of a human heart;

FIG. 3A is an expandable support member of the apparatus in FIGS. 1A-Bin the radially collapsed configuration;

FIG. 3B is the expandable support member of FIG. 3A in the radiallyexpanded configuration;

FIG. 3C is saddle-shaped, three-dimensional configuration of theexpandable support member in the radially expanded configuration;

FIG. 4A is a plan view showing an exploded portion of the expandablesupport member in FIG. 1A;

FIG. 4B is a plan view showing an exploded portion of the expandablesupport member in FIG. 1B and FIG. 3B;

FIG. 5A is a plan view showing an alternative configuration of theexpandable support member in FIG. 4A;

FIG. 5B is a plan view showing another alternative configuration of theexpandable support member in FIG. 5A;

FIG. 5C is a plan view showing another alternative configuration of theexpandable support member in FIG. 5B;

FIG. 5D is a plan view showing an alternative configuration of theexpandable support member in FIG. 5C;

FIG. 6A is an exploded plan view showing an alternative configuration ofan expandable region comprising a portion of the expandable supportmember in FIG. 4A;

FIG. 6B is an exploded plan view showing another alternativeconfiguration of the of the expandable region in FIG. 6A;

FIG. 6C is an exploded plan view showing another alternativeconfiguration of the of the expandable region in FIG. 6B;

FIG. 6D is an exploded plan view showing another alternativeconfiguration of the of the expandable region in FIG. 6C;

FIG. 6E is an exploded plan view showing another alternativeconfiguration of the of the expandable region in FIG. 6D;

FIG. 7 is a perspective view showing an alternative configuration of theexpandable support member in FIGS. 3A-B comprising a plurality ofexpandable units;

FIG. 8 is a perspective view showing one of the expandable units in FIG.7 in a radially collapsed configuration;

FIG. 9 is a process flow diagram illustrating a method for forming aprosthetic valve according to another aspect of the present invention;

FIG. 10A is valve tissue in a beaker used to prepare the prostheticvalve according to the method of FIG. 9;

FIG. 10B is three valve molds used to prepare the prosthetic valveaccording to the method of FIG. 9;

FIG. 10C is an alternative configuration of the expandable supportmember in FIGS. 3A-B used to prepare the prosthetic valve according tothe method of FIG. 9;

FIG. 10D shows sutures used to prepare the prosthetic valve according tothe method of FIG. 9;

FIG. 10E shows a valve leaflet support member used to prepare theprosthetic valve according to the method of FIG. 9;

FIG. 10F shows a holding clamp used to prepare the prosthetic valveaccording to the method of FIG. 9;

FIG. 11 shows the valve tissue in FIG. 10A wrapped around one of thevalve molds;

FIG. 12 shows the valve tissue in FIG. 11 being sutured about the valvemold;

FIG. 13A shows each of the valve molds and corresponding valve tissuesections joined together with the holding clamp in FIG. 10F;

FIG. 13B shows the valve tissue sections in FIG. 13A being suturedtogether;

FIG. 14A shows the valve tissue sections in FIG. 13B sutured together;

FIG. 14B shows a low end of the valve tissue in FIG. 14A being suturedtogether;

FIG. 14C shows the low end of the valve tissue in FIG. 14B being furthersutured together;

FIG. 15A shows the expandable support member of FIG. 10C beingpositioned around the valve tissue in FIG. 14C;

FIG. 15B shows a high end of the valve tissue in FIG. 15A being suturedto the expandable support member;

FIG. 15C shows the low end of the valve tissue in FIG. 15B being suturedto the expandable support member;

FIG. 16 shows an electric welding tip being used to trim and weld downthe expandable support member in FIG. 15C;

FIG. 17 shows a scalpel the valve leaflet support member of FIG. 10Ebeing used to trim excess valve tissue;

FIG. 18 is a process flow diagram illustrating a method for replacing adiseased cardiac valve according to another aspect of the presentinvention;

FIG. 19 is a cross-sectional view showing a guidewire extendingtrans-septally through the human heart of FIG. 2;

FIG. 20 is a cross-sectional view showing the guidewire in FIG. 19extending through the mitral valve into the left ventricle;

FIG. 21 is a cross-sectional view showing a delivery catheter advancedover the guidewire in FIG. 20;

FIG. 22 is a cross-sectional view showing the apparatus of FIG. 1Apositioned at the distal end of the delivery catheter in FIG. 21;

FIG. 23 is a cross-sectional view of a magnified mitral valve showingthe apparatus in FIG. 22 being deployed in the mitral valve with aninflatable member;

FIG. 24 is a cross-sectional view of the mitral valve showing theapparatus of FIG. 1B securely positioned in place of the mitral valve inFIG. 23;

FIG. 25 is a process flow diagram illustrating a method for replacing adiseased cardiac valve according to another aspect of the presentinvention;

FIG. 26 is a cross-sectional view of the mitral valve showing theapparatus of FIG. 1B self-expanding in place of the mitral valve in FIG.23;

FIG. 27 is a cross-sectional view showing the apparatus in FIG. 26implanted in the mitral valve;

FIG. 28 is a cross-sectional view showing an alternative configurationof the delivery catheter in FIG. 26;

FIG. 29 is a cross-sectional view showing the delivery catheter in FIG.28 deploying the apparatus in FIG. 1B;

FIG. 30 is a cross-sectional view showing the apparatus in FIG. 29 beingdeployed in the mitral valve;

FIG. 31 is a cross-sectional view showing the apparatus in FIG. 30deployed in the mitral valve and the delivery catheter in FIG. 30 placedin a non-deployed configuration;

FIG. 32 is a cross-sectional view showing the catheter in FIG. 31 beingremoved from the subject;

FIGS. 33A-B are perspective views showing an alternative configurationof the apparatus in FIG. 1B;

FIGS. 34A-B are perspective views showing the apparatus in FIGS. 33A-Bwithout a bioprosthetic valve (for clarity);

FIGS. 35A-B are perspective views showing a first end portion (FIG. 34A)and a second end portion (FIG. 34B) of the apparatus in FIGS. 34A-B;

FIGS. 36A-B are perspective views showing an alternative configurationof the apparatus in FIGS. 34A-B;

FIGS. 37A-B are a perspective view of the apparatus in FIGS. 34A-Boptionally including an expandable ring disposed about a main bodyportion of the apparatus (FIG. 37A) and first and second expandablerings disposed about the first and second end portions, respectively, ofthe apparatus (FIG. 37B);

FIG. 38 is a schematic illustration showing a locking mechanism of theexpandable rings in FIGS. 37A-B;

FIG. 39 is a process flow diagram illustrating a method for replacing anindwelling bioprosthetic valve in a subject according to another aspectof the present invention;

FIG. 40 is a cross-sectional view showing the apparatus of FIGS. 34A-Bplaced about an inflatable member and being delivered to an indwellingbioprosthetic mitral valve;

FIG. 41 is a cross-sectional magnified view of the apparatus in FIG. 40being deployed in the indwelling bioprosthetic mitral valve;

FIG. 42 is a cross-sectional magnified view showing the apparatus inFIG. 41 deployed within the indwelling bioprosthetic mitral valve;

FIG. 43 is a cross-sectional view showing an alternative configurationof the apparatus in FIGS. 1A-B implanted in an indwelling bioprostheticmitral valve;

FIG. 44 is a cross-sectional view showing the apparatus in FIG. 43implanted in an indwelling bioprosthetic aortic valve and an alternativeconfiguration of the apparatus in FIGS. 33A-36B implanted in anindwelling bioprosthetic mitral valve;

FIG. 45 is a cross-sectional view showing the apparatus in FIG. 44(implanted in an indwelling bioprosthetic mitral valve) implanted in anindwelling bioprosthetic aortic valve;

FIG. 46 is a perspective view showing an alternative configuration ofthe apparatus shown in FIGS. 1A-B;

FIG. 47 is a side view of the apparatus shown in FIG. 46; and

FIG. 48 is a top view of the apparatus shown in FIG. 46.

DETAILED DESCRIPTION

The present invention relates generally to cardiac valve repair andreplacement, and more particularly to an apparatus and method for thecorrection of cardiac valve disorders. As representative of the presentinvention, FIGS. 1A-B illustrate an apparatus 10 comprising anexpandable support member 12 and a prosthetic valve 14 secured therein.The apparatus 10 is for replacing a diseased cardiac valve 16 (FIG. 2)(e.g., a mitral valve 18) by implanting the apparatus (FIGS. 1A-B) overthe native or diseased cardiac valve so that the prosthetic valve 14assumes the valvular function. Although the apparatus 10 is describedbelow for replacing a diseased mitral valve 18 (FIG. 2), it should beunderstood that the apparatus could also be used to replace otherdiseased cardiac valves, such as the tricuspid valve 20, the pulmonaryvalve (not shown), and the aortic valve 250 (FIG. 43).

FIG. 2 schematically illustrates a human heart 22, which includes fourchambers: the right and left atria 24 and 26, respectively, and theright and left ventricles 28 and 30, respectively. The right and leftatria 24 and 26 are divided by the interatrial septum 32. Thethin-walled right atrium 24 receives deoxygenated blood from thesuperior vena cava 34, the inferior vena cava 36, and from the coronarysinus (not shown). The thin-walled left atrium 26 receives oxygenatedblood from pulmonary veins 38. The right and left ventricles 28 and 30pump oxygenated and deoxygenated blood, respectively, throughout thebody, and the pocket-like semilunar pulmonary valve and the aortic valveprevent reflux into the ventricles. Atrial blood is pumped through theatrioventricular orifices, guarded by the tri-leaflet tricuspid valve 20on the right side of the heart 22 and the bi-leaflet mitral valve 18 onthe left side of the heart. The leaflets 40 of the mitral valve 18 areattached to the papillary muscles 42 in the left and right ventricles 30and 28 by chordae tendineae 44. Similarly, the leaflets 46 of thetricuspid valve 20 are attached to the papillary muscles 42 in the leftand right ventricles 30 and 28 by chordae tendineae 44.

As shown in FIGS. 1A-B, one aspect of the present invention includes anapparatus 10 for replacing a diseased cardiac valve. The apparatus 10comprises an expandable support member 12, commonly referred to as astent, and a prosthetic valve 14 secured therein. The expandable supportmember 12 is generally annular in shape and has oppositely disposedfirst and second end portions 48 and 50 and a main body portion 52extending between the end portions. Additionally, the expandable supportmember 12 has a saddle-shaped, three-dimensional (3D) configuration tomimic the 3D shape of a diseased cardiac valve (FIG. 3C). The expandablesupport member 12 (FIGS. 1A-B) has a flexible configuration that allowsthe apparatus 10 to transition between a radially collapsedconfiguration (FIG. 1A) and a radially expanded configuration (FIG. 1B).The flexible and expandable properties of the expandable support member12 facilitate delivery of the apparatus 10, while also allowing theexpandable support member to conform to the convex shape of the mitralvalve annulus 54 (FIG. 12), for example.

All or only a portion of the expandable support member 12 (FIGS. 1A-B)may be made from a medical grade metal or plastic, including shapememory materials, such as Nitinol, stainless steel, and/or titanium. Forexample, all or only a portion of the expandable support member 12 maybe made of a Co—Cr alloy, such as Co-20Cr-15W-10Ni. As described below,the expandable support member 12 may thus be self-expandable ormechanically expandable (e.g., using a balloon) depending upon thematerial used to construct the expandable support member. Additionally,at least a portion of the expandable support member 12 may be made froma bioabsorbable material, such as a magnesium alloy, dendrimers,biopolymers (e.g., thermoplastic starch), polylactides, cellulose, andaliphatic aromatic copolyesters.

The main body portion 52 (FIG. 1A) extends between the first and secondend portions 48 and 50 of the expandable support member 12. The mainbody portion 52 includes an outer circumferential surface 56 oppositelydisposed from an inner circumferential surface 58. As shown in FIG. 1A,a circumferential axis CA extends about or around the outercircumferential surface 56, approximately between the first and secondend portions 48 and 50 of the expandable support member 12.

The main body portion 52 also includes a plurality of wing members 60(FIGS. 3A-B) spaced apart from one another by an expandable region 62.Each of the wing members 60 (FIGS. 4A-B) has an arch-like shape andincludes a first end portion 64, a second end portion 66, and a flexiblemiddle portion 68 extending between the first and second end portions.The first end portion 64 of each of the wing members 60 is substantiallyadjacent the circumferential axis CA of the main body portion 52. Thefirst end portion 64 of each of the wing members 60 can be sharpened ordull (e.g., arrow- or fish hook-shaped). It should be appreciated thatthe first end portion 64 of each of the wing members 60 can include atleast one attachment mechanism (not shown) to facilitate attachment andpositioning of the apparatus 10 in the annulus (not shown in detail) ofthe diseased cardiac valve 16. For example, the attachment mechanism caninclude at least one barb, hook, or other similar means for embeddinginto a section of cardiac tissue (e.g., annular tissue, myocardium,valve leaflet, chordae, etc.).

As described below, the flexible middle portion 68 is resilientlybendable to allow the first end portion 64 of each of the wing members60 to radially expand relative to the outer circumferential surface 56.As shown in FIGS. 4A-B, for example, the first end portion 64 of each ofthe wing members 60 is substantially flush with the outercircumferential surface 56 when the apparatus 10 is in the radiallycollapsed configuration. Additionally, the first end portion 64 of eachof the wing members 60 extends substantially radial to both thecircumferential axis CA and the outer circumferential surface 56 whenthe apparatus 10 is in the radially expanded configuration. In theexpanded configuration, for example, the wing members 60 can bend, flex,or protrude outward so that they are offset from and/or non-coplanarwith (e.g., substantially radial to) the outer circumferential surface56. For instance, the wing members 60 can be offset from the outercircumferential surface 56 by about 1° to about 90° or more.

The second end portion 66 of each of the wing members 60 is integrallyformed with a portion of the main body portion 52. As shown in FIGS.4A-B, for example, the second end portion 66 of each of the wing members60 is integrally formed with the main body portion 52, near the firstand second end portions 48 and 50 of the expandable support member 12.The second end portion 66 can also be integrally formed with the mainbody portion 52 near the circumferential axis CA, as shown in FIG. 5A.The second end portion 66 (FIGS. 4A-B) of each of the wing members 60can additionally or optionally include a plurality of openings 70 tofacilitate attachment of the prosthetic valve 14 to the expandablesupport member 12. Although four circular openings 70 are shown at thesecond end portion 66 of each of the wing members 60, it will beappreciated that the second end portion can include any number and shapeof openings.

The expandable support member 12 can include any number, size, andconfiguration of wing members 60. As illustrated in FIGS. 3A-B, forexample, the apparatus 10 includes eighteen wing members 60 spaced aboutthe main body portion 52 of the expandable support member 12. It shouldbe understood, however, that the expandable support member 12 caninclude more or less than eighteen wing members 60. As shown in FIGS.4A-B and FIGS. 5C-D, for example, a first plurality of wing members 60′can be circumferentially spaced around a lower portion 72 of theexpandable support member 12, and a second plurality of wing members 60″can be circumferentially spaced around an upper portion 74 of theexpandable support member. The first plurality of wing members 60′ canbe symmetrically aligned with the second plurality of wing members 60″(with respect to the circumferential axis CA). Alternatively, the firstplurality of wing members 60′ can be asymmetrically aligned with thesecond plurality of wing members 60″ (with respect to thecircumferential axis CA), as shown in FIG. 5A and FIG. 5C.

Other possible wing member 60 configurations are illustrated in FIGS.5B-D. As shown in FIGS. 5B-C, each of the wing members 60″ comprisingthe second plurality of wing members can have a size less than the sizeof each of the wing members 60′ comprising the first plurality of wingmembers (e.g., ½, ⅓, or ⅔ of the size). For instance, each of the wingmembers comprising the second plurality of wing members 60″ can have asize that is less than about two-thirds the size of the wing memberscomprising the first plurality of wing members 60′. It will beappreciated that each of the wing members 60′ comprising the firstplurality of wing members can alternatively have a size less than thesize of each of the wing members 60″ comprising the second plurality ofwing members. Although the expandable support member 12 is shown ashaving wing members 60 at both the first and second end portions 48 and50, it should be appreciated that only the first end portion or only thesecond end portion of the expandable support member may include aplurality of wing members.

The main body portion 52 of the expandable support member 12 alsoincludes a plurality of expandable regions 62, each of which is spacedbetween the wing members 60 and extends between the first and second endportions 48 and 50 of the expandable support member. In the radiallycollapsed configuration shown in FIG. 4A, each of the expandable regions62 obtains an elongated cylindrical configuration, whereas each of theexpandable regions obtains a trapezoidal configuration in the radiallyexpanded configuration (FIG. 4B).

As illustrated in FIGS. 5A-6E, each of the expandable regions 62 canadditionally or optionally include at least one reinforcing strut member76. The reinforcing strut member 76 can have a variety ofconfigurations. For example, the reinforcing strut member 76 can bediamond-shaped as shown in FIGS. 5C-D. Additionally or optionally, eachof the expandable regions 62 can include two or more strut members 76that extend substantially parallel to the circumferential axis CA. Forexample, each of the expandable regions 62 can include a plurality ofM-shaped (FIG. 6A), W-shaped (FIG. 6B), or A-shaped strut members 76(FIGS. 6C-E).

FIGS. 7-8 illustrate an expandable support member 12′ constructed with asimilar configuration as the expandable support member 12 illustrated inFIGS. 3A-B. As shown in FIG. 7, the expandable support member 12′ can begenerally annular in shape and have oppositely disposed first and secondend portions 48′ and 50′ and a main body portion 52′ extending betweenthe end portions. Additionally, the expandable support member 12′ canhave a saddle-shaped, 3D configuration to mimic the 3D shape of adiseased cardiac valve (FIG. 3C). The expandable support member 12′(FIG. 7) can have a flexible configuration to facilitate transitionbetween a radially collapsed configuration and a radially expandedconfiguration. All or only a portion of the expandable support member12′ may be made from a medical grade metal or plastic, including shapememory materials, such as Nitinol, stainless steel, and/or titanium. Forexample, all or only a portion of the expandable support member 12′ maybe made of a Co—Cr alloy, such as Co-20Cr-15W-10Ni. The expandablesupport member 12′ may be self-expandable or mechanically expandable(e.g., using a balloon), depending upon the material used to constructthe expandable support member. Additionally, at least a portion of theexpandable support member 12′ may be made from a bioabsorbable material,such as a magnesium alloy, dendrimers, biopolymers (e.g., thermoplasticstarch), polylactides, cellulose, and aliphatic aromatic copolyesters.

The main body portion 52′ can extend between the first and second endportions 48′ and 50′ and include an outer circumferential surface 56′oppositely disposed from an inner circumferential surface 58′. As shownin FIG. 7, a circumferential axis CA′ extends about or around the outercircumferential surface 56′, approximately between the first and secondend portions 48′ and 50′ of the expandable support member 12′.

The expandable support member 12′ can be made from a plurality ofinterconnected, expandable units 132 (FIG. 8). In the radially collapsedconfiguration, each of the units 132 has a rectangular configuration;whereas each of the units has trapezoidal configuration (FIG. 7) in theradially expanded configuration. The second end portion 50′ of each ofthe expandable units 132 can include a W-shaped wing member 60′ having afirst end portion 64′ and a spaced apart, flexible second end portion66′.

The first end portion 64′ of each of the wing members 60′ can besubstantially adjacent the second end portion 50′ of the expandablesupport member 12′. The first end portion 64′ of each of the wingmembers 60′ can be sharpened or dull (e.g., arrow or fish hook-shaped).It should be appreciated that the first end portion 64′ of each of thewing members 60′ can include at least one attachment mechanism (notshown) to facilitate attachment and positioning of the expandablesupport member 12′ in the annulus (not shown in detail) of the diseasedcardiac valve 16. For example, the attachment mechanism can include atleast one barb, hook, or other similar means for embedding into asection of cardiac tissue (e.g., annular tissue, valve leaflet, chordae,etc.).

The second end portion 66′ of each of the wing members 60′ can beintegrally formed with a portion of the main body portion 52′. As shownin FIGS. 7-8, for example, the second end portion 66′ of each of thewing members 60′ can be integrally formed with the main body portion 52′near the circumferential axis CA′. The first end portion 64′ of the wingmembers 60′, the second end portion 66′ of the wing members, or both,can additionally or optionally include a plurality of openings (notshown) to facilitate attachment of the prosthetic valve 14 to theexpandable support member 12′.

The second end portion 66′ of each of the wing members 60′ isresiliently bendable to allow the first end portion 64′ to radiallyexpand relative to the outer circumferential surface 56′. As shown inFIG. 7, for example, the first end portion 64′ of each of the wingmembers 60′ can be substantially flush with the outer circumferentialsurface 56′ when the expandable support member 12′ is in the radiallycollapsed configuration. Additionally, the first end portion 64′ of eachof the wing members 60′ can extend substantially radial to both thecircumferential axis CA′ and the outer circumferential surface 56′ whenthe expandable support member 12′ is in the radially expandedconfiguration.

It will be appreciated that the expandable support member 12′ caninclude any number, size, and configuration of wing members 60′. Forexample, the expandable support member 12′ can include a plurality ofwing members 60′ spaced around only the first end portion 48′ or,alternatively, a plurality of wing members spaced around both the firstend portion and the second end portion 50′. It will also be appreciatedthat the expandable support member 12′ can additionally or optionallyinclude at least one reinforcing strut member 76, as shown in FIGS.5A-6E and described above. Although the expandable support member 12′ isshown as having wing members 60 and 60′ at both the first and second endportions 48′ and 50′, it should be appreciated that only the first endportion or only the second end portion of the expandable support membermay include a plurality of wing members.

It will be appreciated that the expandable support member 12 and 12′ caninclude a layer of biocompatible material (not shown) separatelycovering at least a portion of the expandable support member and/or oneor more of the wing members 60 and 60′. The layer of biocompatiblematerial may be synthetic, such as DACRON (Invista, Wichita, Kans.),woven velour, polyurethane, polytetrafluoroethylene (PTFE), expandedPTFE, GORE-TEX (W. L. Gore & Associates, Flagstaff, Ariz.), orheparin-coated fabric. Alternatively, the layer may be a biologicalmaterial, such as bovine, porcine or equine pericardium, peritonealtissue, an allograft, a homograft, a patient graft, or a cell-seededtissue. The layer may be attached around the outer circumferentialsurface 56 and 56′ of the expandable support member 12 and 12′ in piecesor interrupted sections to allow the wing members 60 and 60′ to easilyexpand. By covering a portion of the expandable support member 12 and12′ with a layer of biocompatible material, the hemocompatibility of theapparatus 10 may be improved.

The expandable support member 12 and 12′ may additionally or optionallyinclude at least one therapeutic agent for eluting into thecardiovascular tissue and/or blood stream. The therapeutic agent may becapable of preventing a variety of pathological conditions including,but not limited to, hypertension, hypotension, arrhythmias, thrombosis,stenosis and inflammation. Accordingly, the therapeutic agent mayinclude at least one of an anti-arrhythmic agent, an anti-hypertensive,an anti-hypotensive agent, an anticoagulant, an antioxidant, afibrinolytic, a steroid, an anti-apoptotic agent, an anti-mineralizationagent, an anti-calcification agent, and/or an anti-inflammatory agent.

Optionally or additionally, the therapeutic agent may be capable oftreating or preventing other diseases or disease processes, such asmicrobial infections and heart failure. In these instances, thetherapeutic agent may include an inotropic agent, a chronotropic agent,an anti-microbial agent, and/or a biological agent such as a cell,peptide, or nucleic acid. The therapeutic agent can be linked to asurface of the expandable support member 12 and 12′, embedded andreleased from within polymer materials, such as a polymer matrix, orsurrounded by and released through a carrier.

As shown in FIGS. 1A-B, the prosthetic valve 14 is secured within themain body portion 52 of the expandable support member 12 by sutures orother suitable means. In one example of the present invention, theprosthetic valve 14 can comprise a stentless, substantially dehydratedbioprosthetic valve. By “stentless” it is meant that the leaflets of theprosthetic valve 14 are not reinforced with a support structure, such asa stent or other similar structure. Other examples of prosthetic valvesare known in the art, such as the valves disclosed in U.S. Pat. No.5,156,621, which is hereby incorporated by reference in its entirety.

A substantially dehydrated bioprosthetic valve 14 may be fixed andpreserved using a variety of known methods. The use of chemicalprocesses for the fixation and preservation of biological tissues havebeen described and are readily available in the art. For example,glutaraldehyde, and other related aldehydes have seen widespread use inpreparing cross-linked biological tissues. Glutaraldehyde is a fivecarbon aliphatic molecule with an aldehyde at each end of the chain,rendering it bifunctional. These aldehyde groups react underphysiological conditions with primary amine groups on collagen moleculesresulting in the cross-linking of collagen containing tissues. Methodsfor glutaraldehyde fixation of biological tissues have been extensivelydescribed and are well known in the art. In general, a tissue sample tobe cross-linked is simply contacted with a glutaraldeyde solution for aduration effective to cause the desired degree of cross-linking withinthe biological tissue being treated.

Many variations and conditions have been applied to optimizeglutaraldehyde fixation procedures. For example, lower concentrationshave been found to be better in bulk tissue cross-linking compared tohigher concentrations. It has been proposed that higher concentrationsof glutaraldehyde may promote rapid surface cross-linking of the tissue,generating a barrier that impedes or prevents the further diffusion ofglutaraldehdye into the tissue bulk. For most bioprosthesisapplications, the tissue is treated with a relatively low concentrationglutaraldehyde solution, e.g., typically between 0.1%-5%, for 24 hours(or more) to ensure optimum fixation. Various other combinations ofglutaraldehyde concentrations and treatment times will also be suitabledepending on the objectives for a given application. Examples of suchother combinations include, but are not limited to, U.S. Pat. Nos.6,547,827, 6,561,970, and 6,878,168, all of which are herebyincorporated by reference in their entirety.

In addition to bifunctional aldehydes, many other chemical fixationprocedures have been described. For example, some methods employpolyethers, polyepoxy compounds, diisocyanates, and azides. These andother approaches available to the skilled individual in the art fortreating biological tissues are suitable for cross-linking vasculargraft tissue according to the present invention.

The substantially dehydrated bioprosthetic valve 14 may also be treatedand preserved with a dry tissue valve procedure as described in U.S.Pat. No. 6,534,004, the entire contents of which are hereby incorporatedby reference. Furthermore, the substantially dehydrated bioprostheticvalve 14 may be treated with anti-calcification solutions, such asXENOLOGIX treatment (Edwards Lifesciences, Irvine, Calif.) or theSYNERGRAF (CryoLife, Inc., Kennesaw, Ga.) treatment process, and/oranti-calcification agents, such as a-amino oleic acid.

The substantially dehydrated bioprosthetic valve 14 can be made with onepiece of pericardial tissue, for example. Where a single piece ofpericardial tissue is used, a seam may be formed by suturing the ends ofthe tissue. Alternatively, the substantially dehydrated bioprostheticvalve 14 can be made with two pieces of pericardial tissue, one of whichwill form the first leaflet and the other forms the second leaflet ofthe valve. Where two pieces of pericardial tissue are used, it isnecessary to suture the tissue in two locations, thereby forming twoseams. The seams are always placed at what will be the commissuralsections of the valve 14, where the first leaflet meets the secondleaflet. It will be appreciated that the prosthetic valve 14 can be madewith three or more pieces of tissue as well.

Another method 100 for making the prosthetic valve 14 (e.g., asubstantially dehydrated bioprosthetic valve) is illustrated in FIG. 9.As shown in FIG. 9, one step of the method 100 can include preparingvalve tissue 110 (FIG. 10A) at Step 102. The valve tissue used toprepare the prosthetic valve 14 can comprise any one or combination ofbiological tissue(s), such as bovine, porcine or equine pericardium,peritoneal tissue, an allograft, a homograft, a patient graft, or acell-seeded tissue. The valve tissue 110 can be chemically-treated(e.g., cross-linked) prior to use (as described above). For example, thetissue 110 used to form the prosthetic valve 14 can comprisecross-linked equine pericardium tissue.

To prepare the valve tissue 110, a variety of materials and componentscan first be assembled. As shown in FIGS. 10A-F, the materials andcomponents can include the valve tissue 110 (FIG. 10A), a plurality ofvalve molds 112 (FIG. 10B), an expandable support member 12″ (FIG. 10C),sutures 114 (FIG. 10D) (e.g., 4-0 prolene sutures), a silicone valveleaflet support member 116 (FIG. 10E), and a holding clamp 118 (FIG.10F). Although the expandable support member 12″ shown in FIG. 10C has aW-shaped configuration, it will be appreciated that the expandablesupport member can have any other desired configuration, such as theconfiguration of the expandable support member 12 and 12′ shown in FIGS.1A-B and FIGS. 7-8 (respectively). Other materials and components thatmay be needed for the method 100 can include one or more scalpels 120(FIG. 17), one or more hemostats (not shown), one or more surgicaltowels 122 (FIG. 12), and scissors 124.

To prepare the valve tissue 110 (e.g., cross-linked equine pericardium)(FIG. 11), the tissue is measured and cut into a number of strips equalto the number of valve molds 112. For example, three strips of tissue110 each having a width of about 4 cm can be prepared. As shown in FIG.11, each of the tissue strips 110 can then be wrapped around a separateone of the valve molds 112. The tissue 110 can then be trimmed (e.g.,using a surgical knife) such that the two ends of the tissue meetwithout any overlap (indicated by boxed region in FIG. 11). The ends ofeach of the tissue strips 110 can then be sutured to form a sleeve-likeconfiguration around each of the valve molds 112. As shown in FIG. 12,for example, suturing can begin with three or four knots 114 followed bythe first stitch. The suture 114 density can be controlled within about1.25 mm to about 1.5 mm per stitch, and each stitch can be about 3 mmwide.

At Step 104, the valve tissue 110 can be sewn together to form astentless valve. As shown in FIG. 13A, formation of the stentless valvecan begin by joining each of the valve molds 112 together such that eachsuturing line is aligned with an exterior midline of each of the valvemolds. Next, the holding clamp 118 is placed around one end of each ofthe valve molds 112 to form a high end 126 and a low end 128. Asindicated by the boxed region in FIGS. 13A-B, each of the tissue sleeves110 is positioned adjacent one another and then sutured. The suture 114can start with about 3 to four knots, which serve as an alignment pointfor the expandable support member 12″. The suture 114 density can becontrolled within about 1.25 mm to about 1.5 mm per stitch, and eachstitch can be about 3 mm wide. About 3 mm of each of the tissue sleeves110 at the high end 126 should not be sutured to facilitate laterattachment of the stentless valve to the expandable support member 12″.

Next, the low end 128 of the stentless valve can be closed. As shown inFIGS. 14A-C, the tissue 110 can be moved downward (i.e., away from theholding clamp 118) so that a desired amount of the tissue at the low end128 extends beyond each of the valve molds 112. For example, the tissue110 can be moved about 15 mm. After moving the tissue 110 downward, thepliable tissue at the low end 128 can be partially closed as shown inFIG. 14C. The suture 114 density can be controlled within about 1.25 mmto about 1.5 mm per stitch, and each stitch can be about 3 mm wide.

At Step 106, the stentless valve can be attached to the expandablesupport member 12″. As shown in FIG. 15A, the expandable support member12″ can be evenly positioned over the tissue 110 so that each sutureline 114 is aligned with an alternating peak of the expandable supportmember (indicated by oval in FIG. 15A). Care should be taken to makesure the expandable support member 12″ is evenly aligned with the tissue110. Using the W-shaped expandable support member 12″ shown in FIGS.15A-C, for example, care should be taken to ensure that each tissuesection 110 includes three V-shaped “units” of the expandable supportmember.

As shown in FIG. 15B, the tissue 110 located at the high end 126 canthen be flipped downward over a portion of the expandable support member12″ to form a lip. The lip can be carefully sutured to ensure that thesuture penetrates all layers of the tissue 110. Additionally, careshould be taken to place stitches 114 (e.g., about 3 stitches) on everypeak of the expandable support member 12″, as well as one or morestitches at every two peak ends. As shown in FIG. 15C, the free tissue110 at the low end 128 of the expandable support member 12″ can then beflipped to form a lip and then sutured to secure the lower end to theexpandable support member (as described above).

After suturing the high and low ends 126 and 128, the newly-formedprosthetic valve 14 can be prepared for implantation at Step 108. Anyfree end(s) of the suture(s) 114 can be trimmed using scissors 124, forexample. The expandable support member 12″ can then be trimmed andwelded for a sufficient period of time using an electric welding tip 130(FIG. 16) at about 650° F. to about 660° F. Examples of electric weldingdevices (not shown) and tips 130 are known in the art and can includethe WELLER EC2002M Soldering Station, for example. Next, any unwantedremaining tissue 110 at the low end 128 can be trimmed as needed.

To trim any tissue 110 remaining at the high end 126, the silicone valveleaflet support 116 can be used as shown in FIG. 17. For example, sparetissue 110 can be trimmed using a scalpel 120 (e.g., a #12 scalpel) tomake the ends of the leaflets uniform with one another. Additionally,the spare tissue 110 can be trimmed such that each of the leaflets isangled downward (as measured from the circumference to the central axisof the valve 14). For example, each of the leaflets can be trimmed sothat the end of each of the leaflets is angled downward at about 2 to 5degrees. Once the construction of the prosthetic valve 14 has beencompleted, the valve can be sterilized and stored under wet or dry(i.e., dehydrated) conditions.

FIG. 18 illustrates another aspect of the present invention comprising amethod 78 for replacing a diseased cardiac valve 16, such as a diseasedmitral valve 18. Although the method 78 is illustrated below using apercutaneous approach, it will be appreciated that other approaches canbe used for replacing the diseased cardiac valve 16. Examples of suchalternative approaches can include, but are not limited to, open heartsurgery, thoracotomy, thoracoscopic, robotic implantation, left atrialdome insertion, left atrial appendage insertion, transapical insertion,insertion via a pulmonary vein 38, and other minimally invasivetechniques known in the art.

One step of the method 78 includes providing an apparatus 10 at Step 80.For example, the apparatus 10 can be constructed as illustrated in FIGS.1A-4B. Prior to placement of the apparatus 10, the dimensions of thediseased mitral valve 18 are determined using known imaging techniquesincluding, for example, magnetic resonance imaging (MRI), fluoroscopy,echocardiography (e.g., TEE or TTE imaging), computed tomography (CT),angiography, ultrasound, or a combination thereof. After determining thedimensions of the diseased mitral valve 18, an appropriately-sizedapparatus 10 having dimensions that correspond to the dimensions of thediseased mitral valve is selected.

To enable delivery and deployment of the apparatus 10 in the diseasedmitral valve 18, the apparatus 10 is positioned about an inflatablemember 90 (FIG. 23) in the radially collapsed configuration at Step 82.The inflatable member 90 can include a balloon, for example, capable ofexpanding the main body portion 52 into full and complete contact withthe annulus 54 of the diseased mitral valve 18. Additionally, theinflatable member 90 can be shaped to conform to the cross-sectionalconfiguration of the main body portion 52. After securing the apparatus10 about the inflatable member 90 in the radially collapsedconfiguration, the apparatus is then loaded into the end of a deliverycatheter 92 at Step 84 in a known manner.

Next, a guidewire 94 is inserted into the vasculature via a femoral vein(not shown) or jugular vein (not shown) and, under image guidance (e.g.,fluoroscopy, ultrasound, MRI, CT, angiography, or a combinationthereof), respectively steered through the vasculature into the inferiorvena cava 36 or superior vena cava 34. The guidewire 94 is then passedacross the right atrium 24 so that the distal end 96 of the guidewirepierces the interatrial septum 32 as shown in FIG. 19. The guidewire 94is extended across the left atrium 26 and then downward through thediseased mitral valve 18 so that the distal end 96 of the guidewire issecurely positioned in the left ventricle 30 (FIG. 20).

After the guidewire 94 is appropriately positioned in the heart 22, thedelivery catheter 92 is passed over the guidewire at Step 86 (FIG. 21).After the delivery catheter 92 is positioned as shown in FIG. 21, theapparatus 10 is attached to the proximal end (not shown) of theguidewire 94. A positioning wire (not shown) or other similar deviceuseful for advancing the apparatus 10 over the guidewire 94 is thenattached to the apparatus. An axial force is then applied to thepositioning wire so that the apparatus 10 is passed over the guidewire94 and positioned at the distal end 98 of the delivery catheter 92 (FIG.22).

Upon reaching the distal end 98 of the delivery catheter 92, theapparatus 10 is deployed at Step 88. As shown in FIG. 23, the apparatus10 is positioned adjacent the mitral annulus 54 and progressively freedfrom the delivery catheter 92. As the apparatus 10 is progressivelyfreed from the delivery catheter 92, the position of the apparatus inthe mitral annulus 54 can be monitored, controlled, and/or qualityassured by imaging systems of various kinds For example, X-ray machines,angiography, fluoroscopic machines, ultrasound, CT, MRI, positronemission tomography (PET), and other imaging devices may be used.

After positioning the apparatus 10 as shown in FIG. 23, the inflatablemember 90 is inflated using a suitable inflation medium, such air or asaline solution. Inflating the inflatable member 90 pushes the main bodyportion 52 of the expandable support member 12 radially outward intoengagement with the mitral annulus 54 and, simultaneously, causes thewing members 60′ and 60″ to radially expand. As shown in FIG. 24, forexample, the first end portion 64 of each of the wing members 60′comprising the first plurality of wing members moves radially outwardfrom the outer circumferential surface 56 into contact with the mitralleaflets 40 and the chordae (not shown); although, it should beappreciated that the wing members may additionally or alternatively moveinto contact with a portion of the annulus 54. Additionally, the firstend portion 64 of each of the wing members 60″ comprising the secondplurality of wing members moves radially outward into contact with theannulus 54.

With the apparatus 10 in the radially expanded configuration, the firstand second plurality of wing members 60′ and 60″ respectively embracethe inferior and superior aspects of the mitral valve 18 and,consequently, secure the apparatus in place of the diseased mitral valve18. Additionally, the radially expansive force of the main body portion52 serves to secure the apparatus 10 in the mitral valve 18. Blood cannow flow through the expandable support member 12 and contact thesubstantially dehydrated bioprosthetic valve 14. As blood contacts thevalve 14, the interstices of the valve are re-hydrated and cause thevalve to obtain its original (or substantially original) properties andassume normal (or substantially normal) blood flow performance. Itshould be appreciated that the prosthetic valve 14 may not bere-hydrated with blood where the prosthetic valve comprises a standard(i.e., non-dehydrated) bioprosthetic valve (e.g., made of porcinetissue). With the apparatus 10 fully deployed, the inflatable member 90is deflated, moved out of the mitral valve annulus 54, and the procedurecompleted.

In another aspect of the present invention, a method 78 _(a) (FIG. 25)is provided for replacing a diseased cardiac valve 16 (e.g., a diseasedmitral valve 18). The steps of the method 78 _(a) are identical to thesteps of the method 78 shown in FIG. 18, except where as describedbelow. In FIG. 25, steps that are identical to steps in FIG. 18 use thesame reference numbers, whereas steps that are similar but not identicalcarry the suffix “a”. Although the method 78 _(a) is illustrated belowusing a percutaneous approach, it will be appreciated that otherapproaches can be used for replacing the diseased cardiac valve 16.Examples of such alternative approaches can include, but are not limitedto, open heart surgery, thoracotomy, left atrial dome insertion, leftatrial appendage insertion, transapical insertion, insertion via apulmonary vein 38, and other minimally invasive techniques known in theart.

One step of the method 78 _(a) includes providing an apparatus 10 atStep 80. For example, the apparatus 10 can have a configuration asillustrated in FIGS. 1A-4B and be made of a self-expandable material,such as Nitinol. Prior to placement of the apparatus 10, the dimensionsof the diseased mitral valve 18 are determined using known imagingtechniques, as described above. After determining the dimensions of thediseased mitral valve 18, an appropriately-sized apparatus 10 havingdimensions that correspond to the dimensions of the diseased mitralvalve is selected.

To enable delivery and deployment of the apparatus 10 in the diseasedmitral valve 18, the apparatus 10 is placed in the radially collapsedconfiguration and then loaded into a delivery catheter 92 at Step 84_(a). Next, a guidewire 94 is inserted into the vasculature via afemoral vein (not shown) or jugular vein (not shown) and, under imageguidance (e.g., fluoroscopy, ultrasound, MRI, CT, angiography, or acombination thereof), respectively steered through the vasculature intothe inferior vena cava 36 or superior vena cava 34. The guidewire 94 isthen passed across the right atrium 24 so that the distal end 96 of theguidewire pierces the interatrial septum 32 (FIG. 19). The guidewire 94is extended across the left atrium 26 and then downward through thediseased mitral valve 18 so that the distal end 96 of the guidewire issecurely positioned in the left ventricle 30 (FIG. 20).

After the guidewire 94 is appropriately positioned in the heart 22, thedelivery catheter 92 is passed over the guidewire at Step 86 (FIG. 21).After the delivery catheter 92 is positioned as shown in FIG. 21, theapparatus 10 is attached to the proximal end (not shown) of theguidewire 94. A positioning wire (not shown) or other similar deviceuseful for advancing the apparatus 10 over the guidewire 94 is thenattached to the apparatus. An axial force is then applied to thepositioning wire so that the apparatus 10 is passed over the guidewire94 and positioned at the distal end 98 of the delivery catheter 92 (notshown).

Upon reaching the distal end 98 of the delivery catheter 92, theapparatus 10 is deployed at Step 88 _(a). As shown in FIG. 26, theapparatus 10 is positioned adjacent the mitral annulus 54 andprogressively freed from the delivery catheter 92. As the apparatus 10is progressively freed from the delivery catheter 92, the position ofthe apparatus in the mitral annulus 54 can be monitored, controlled,and/or quality assured by imaging systems of various kinds. For example,X-ray machines, angiography, fluoroscopic machines, ultrasound, CT, MRI,PET, and other imaging devices may be used.

Progressively withdrawing the delivery catheter 92 allows the second endportion 50 of the expandable support member 12 to expand. As the secondend portion 50 expands, the first end portion 64 of each of the wingmembers 60′ comprising the first plurality of wing members movesradially outward from the outer circumferential surface 56 into contactwith the mitral leaflets 40 and the chordae (not shown); although, itshould be appreciated that the wing members may additionally oralternatively move into contact with a portion of the annulus 54.Continually withdrawing the delivery catheter 92 then allows the mainbody portion 52 of the expandable support member 12 to engage the mitralannulus 54. As the delivery catheter 92 is finally removed from over theapparatus 10, the first end portion 64 of each of the wing members 60″comprising the second plurality of wing members moves radially outwardinto contact with the annulus 54 (FIG. 27).

With the apparatus 10 in the radially expanded configuration, the firstand second plurality of wing members 60′ and 60″ respectively embracethe inferior and superior aspects of the mitral valve 18 and,consequently, secure the apparatus in place of the diseased mitral valve18. Additionally, the radially expansive force of the main body portion52 serves to secure the apparatus 10 in the mitral valve 18. Blood cannow flow through the expandable support member 12 and contact thesubstantially dehydrated bioprosthetic valve 14. As blood contacts thevalve 14, the interstices of the valve are re-hydrated and cause thevalve to obtain its original (or substantially original) properties andassume normal (or substantially normal) blood flow performance. Itshould be appreciated that the prosthetic valve 14 may not bere-hydrated with blood where the prosthetic valve comprises a standard(i.e., non-dehydrated) bioprosthetic valve (e.g., made of porcinetissue).

FIGS. 28-32 illustrate an alternative method 78 _(a) for replacing adiseased cardiac valve 16 (e.g., a diseased mitral valve 18). The method78 _(a) is identical to method (FIG. 25) described above, except thatthe delivery catheter 92′ used to deliver the apparatus 10 has adifferent configuration than the delivery catheter 92 illustrated inFIGS. 26-27 and described above.

As shown in FIGS. 28-32, the delivery catheter 92′ comprises a main bodyportion 134 that is similar or identical to the delivery catheter 92described above. For example, the main body portion 134 has anelongated, tube-like configuration with a proximal end (not shown) and adistal end 98′. The delivery catheter 92′ also includes a conical distaltip 136 that is operably connected to a rod-like positioning member 138(FIG. 29). As described in more detail below, the positioning member 138extends longitudinally through the delivery catheter 92′ and can becontrolled or manipulated (e.g., using tactile force) at its proximalend (not shown) to engage or disengage the distal tip 136 with or fromthe distal end 98′ of the delivery catheter.

The distal tip 136 includes oppositely disposed first and second ends140 and 142 and a cavity 144 (FIG. 29) extending between the first andsecond ends. The first end 140 includes a central aperture (not shown indetail) for receiving the distal end 96 of the guidewire 94. The secondend 142 is capable of mating with the distal end 98′ of the deliverycatheter 92′. The second end 142 of the distal tip 136 has a diametersufficient to permit at least a portion of the apparatus 10 to bedisposed in a portion of the cavity 144 when the apparatus is in theradially collapsed configuration (i.e., during deployment). The distaltip 136 can have a rigid or semi-rigid configuration and be made of thesame or similar material as the main body portion 134 of the deliverycatheter 92′.

To replace a diseased cardiac valve 16, such as the mitral valve 18, anapparatus 10 that is similar or identical to the one illustrated inFIGS. 1A-4B and made of a self-expandable material (e.g., Nitinol) isprovided at Step 80. The apparatus 10 is then placed in the radiallycollapsed configuration and then loaded into the delivery catheter 92′at Step 84 _(a). To load the apparatus 10 into the delivery catheter92′, the apparatus is placed at the proximal end of the deliverycatheter and then advanced over the positioning member 138 to the distalend 98′. Prior to advancing the apparatus 10 to the distal end 98′,however, the second end 142 of the distal tip 136 is mated with thedistal end so that the distal end of the delivery catheter 92′ has abullet-shaped configuration (FIG. 28).

Next, a guidewire 94 is inserted into the vasculature via a femoral vein(not shown) or jugular vein (not shown) and, under image guidance (e.g.,fluoroscopy, ultrasound, MRI, CT, angiography, or a combinationthereof), respectively steered through the vasculature into the inferiorvena cava 36 or superior vena cava 34. The guidewire 94 is then passedacross the right atrium 24 so that the distal end 96 of the guidewirepierces the interatrial septum 32 (as described above). The guidewire 94is extended across the left atrium 26 and then downward through thediseased mitral valve 18 so that the distal end 96 of the guidewire issecurely positioned in the left ventricle 30.

After the guidewire 94 is appropriately positioned in the heart 22, thedelivery catheter 92′ is passed over the guidewire 94 at Step 86 untilthe delivery catheter is positioned as shown in FIG. 28. It will beappreciated that that the apparatus 10 may alternatively be delivered tothe distal end 98′ of the delivery catheter 92′ by sliding the deliverycatheter over the guidewire 94, attaching the apparatus to the proximalend of the guidewire, and then advancing the apparatus to the distal endof the delivery catheter.

Next, an axial force is applied to the proximal end of the positioningmember 138 (e.g., using tactile means). Application of the axial forcecauses the distal tip 136 to disengage from the distal end 98′ of thedelivery catheter 92′ and move downward into the left atrium 26(indicated by arrow in FIG. 29). Downward movement of the distal tip 136allows the second end portion 50 of the expandable support member 12 toexpand. As the second end portion 50 expands, the first end portion 64of each of the wing members 60′ comprising the first plurality of wingmembers moves radially outward from the outer circumferential surface 56into contact with the mitral leaflets 40 and the chordae (not shown);although, it should be appreciated that the wing members mayadditionally or alternatively move into contact with a portion of theannulus 54.

At Step 88 _(a), the delivery catheter 92′ is continually withdrawn toallow the apparatus 10 to expand into the annulus 54. As the apparatus10 is progressively freed from the delivery catheter 92′, the positionof the apparatus in the mitral annulus 54 can be monitored, controlled,and/or quality assured by imaging systems of various kinds. For example,X-ray machines, angiography, fluoroscopic machines, ultrasound, CT, MRI,PET, and other imaging devices may be used. Progressively withdrawingthe delivery catheter 92′ allows the second end portion 50 of theexpandable support member 12 to expand.

As the second end portion 50 expands, the first end portion 64 of eachof the wing members 60′ comprising the first plurality of wing membersmoves radially outward from the outer circumferential surface 56 intocontact with the mitral leaflets 40 and the chordae (not shown);although, it should be appreciated that the wing members mayadditionally or alternatively move into contact with a portion of theannulus 54. Continually withdrawing the delivery catheter 92′ thenallows the main body portion 52 of the expandable support member 12 toengage the mitral annulus 54. As the delivery catheter 92′ is finallyremoved from over the apparatus 10, the first end portion 64 of each ofthe wing members 60″ comprising the second plurality of wing membersmoves radially outward into contact with the annulus 54 (FIG. 30).

With the apparatus 10 in the radially expanded configuration, the firstand second plurality of wing members 60′ and 60″ respectively embracethe inferior and superior aspects of the mitral valve 18 and,consequently, secure the apparatus in place of the diseased mitral valve18. Additionally, the radially expansive force of the main body portion52 serves to secure the apparatus 10 in the mitral valve 18. Blood cannow flow through the expandable support member 12 and contact thesubstantially dehydrated bioprosthetic valve 14. As blood contacts thevalve 14, the interstices of the valve are re-hydrated and cause thevalve to obtain its original (or substantially original) properties andassume normal (or substantially normal) blood flow performance. Itshould be appreciated that the prosthetic valve 14 may not bere-hydrated with blood where the prosthetic valve comprises a standard(i.e., non-dehydrated) bioprosthetic valve (e.g., made of porcinetissue).

After the apparatus 10 has been deployed in the mitral valve 18, anaxial force is applied to the proximal end of the positioning member 138so that the second end 142 of the distal tip 136 is drawn toward themain body portion 134 and engages the distal end 98 of the deliverycatheter 92′ (FIG. 31). As shown in FIG. 32, the delivery catheter 92′and the guidewire 94 are then removed from the left atrium 26 and theprocedure completed.

Another aspect of the present invention is illustrated in FIGS. 33A-38B.The apparatus 10 _(b) is identically constructed as the apparatus 10shown in FIGS. 1A-B, except where as described below. In FIGS. 33A-38B,structures that are identical as structures in FIGS. 1A-B use the samereference numbers, whereas structures that are similar but not identicalcarry the suffix “b”.

Implantation of bioprosthetic cardiac valves to treat hemodynamicallysignificant valvular disease has become an increasingly commonprocedure. Replacement of diseased or dysfunctional bioprosthetic valvesreduces the morbidity and mortality associated with valvular disease ordysfunction, but comes at the expense of risking complications unique tothe implanted or indwelling bioprosthetic device. These complicationsinclude valve failure due to calcification or stenosis/fibrosis,valvular endocarditis, valvular thrombosis, thromboembolism, mechanicalhemolytic anemia, and anticoagulant-related hemorrhage. Whenbioprosthetic valves fail, their removal and replacement entails ahighly complicated and invasive procedure. As described in more detailbelow, the apparatus 10 _(b) of the present invention can advantageouslybe used to replace a previously-implanted or indwelling bioprostheticvalve 200 (FIG. 40) that has failed without the need for removal of thefailed bioprosthetic valve. Consequently, the present invention assistsin helping subjects with failed bioprosthetic valves avoid the numerouspotential complications and hardships often associated with replacingsuch failed devices.

As shown in FIGS. 33A-34B, an apparatus 10 _(b) for replacing anindwelling or previously-implanted bioprosthetic valve 200 can comprisean expandable support member 12 (FIGS. 34A-B) and a bioprosthetic valve202 (FIGS. 33A-B) secured therein. Bioprosthetic valves are well knownin the art and can generally comprise a frame 204 having at least twocommissural portions 206 (e.g., posts) spaced apart by a first distanceD1 (FIG. 33B). Bioprosthetic valves also generally include a tissueportion comprising a plurality of leaflets, all or a portion of whichcan be made of a synthetic or biological material. For clarity, thebioprosthetic valve 200 shown in FIGS. 34A-37B does not include a tissueportion.

As mentioned above, the apparatus 10 _(b) can include an expandablesupport member 12, commonly referred to as a stent, and a bioprostheticvalve 202 secured therein. The expandable support member 12 can have asaddle-shaped, 3-D configuration and include a first end portion 48, asecond end portion 50 _(b), and a main body portion 52 _(b) extendingbetween the first and second end portions. The main body portion 52 _(b)can include an outer circumferential surface 56 _(b) and acircumferential axis CA extending about the outer circumferentialsurface. As described above, all or only a portion of the expandablesupport member 12 may be made from a medical grade metal or plastic(e.g., shape memory materials). For example, all or only a portion ofthe expandable support member 12 may be made of a Co—Cr alloy, such asCo-20Cr-15W-10Ni. The expandable support member 12 may beself-expandable or mechanically expandable (e.g., using a balloon),depending upon the material used to construct the expandable supportmember.

As shown in FIGS. 34A-B, the second end portion 50 _(b) of theexpandable support member 12 can include at least two flexible archmembers 208 spaced apart by a second distance D2. The second distance D2can be about equal to the first distance D1 so that the at least twoarch members 208 can securely engage the commissural portions 206 (e.g.,posts) of the indwelling bioprosthetic valve 200. The flexible archmembers 208 can move from a collapsed configuration to an expandedconfiguration when the apparatus 10 _(b) is in the radially collapsedand expanded configurations, respectively. In the collapsedconfiguration (not shown), the flexible arch members 208 can beco-planar with the outer circumferential surface 56 _(b) (and extendradial to the circumferential axis CA) so that the apparatus 10 _(b) canbe readily moved into the indwelling bioprosthetic valve 200 fordeployment. In the expanded configuration (FIGS. 34A-B), the flexiblearch members 208 can bend, flex, or protrude outward so that they areoffset from and/or non-coplanar with (e.g., substantially radial to) theouter circumferential surface 56 _(b). For example, the flexible archmembers 208 can be offset from the outer circumferential surface 56 _(b)by about 1° to about 90° or more. As described in more detail below,expansion or flexion of the arch members 208 can anchor each of the archmembers to a respective commissural portion 206 (e.g., post) of theindwelling bioprosthetic valve 200 to prevent or mitigate migration ofthe apparatus 10 _(b) once implanted.

The flexible arch members 208 can have any configuration (e.g., shapeand size) to facilitate engagement and anchoring of the arch memberswith the commissural portions 206 of the indwelling bioprosthetic valve200. As shown in FIGS. 34A-B, for example, the arch members 208 can havea U-shaped configuration. It will be appreciated, however, that theflexible arch members 208 can have the same or different configuration.The arch members 208 can be securely attached to the second end portion50 _(b) of expandable support member 12 at at least one attachment pointby any suitable means known in the art, such as soldering, an adhesive,etc. For example, each of the arch members 208 can be separatelyattached to the second end portion 50 _(b) at alternating expandableregions 62 _(b) of the expandable support member 12. Alternatively, theflexible arch members 208 can be integrally formed with the second endportion 50 _(b) of the expandable support member 12. For example, theflexible arch members 208 can be a fluid extension of the material usedto form the expandable support member 12. It will be appreciated thatthe arch members 208 can be attached to any section or portion of thesecond end portion 50 _(b) of the expandable support member 12, and thatthe flexible arch members can be made of the same or different material(or materials) from which the expandable support member is made.

One example of an apparatus 10 _(b) having first, second, and thirdflexible arch members 208′, 208″, and 208′″ is shown in FIGS. 34A-35B.The apparatus 10 _(b) can be used to replace an indwelling bioprostheticvalve 200 having first, second, and third commissural portions 206′,206″, and 206′″ (e.g., posts) spaced apart by third, fourth, and fifthdistances D3, D4 and D5. Each of the first, second, and third flexiblearch members 208′, 208″, and 208′″ can have a U-shaped configuration andbe connected to alternating expandable regions 62 _(b) at the second endportion 50 _(b) of the expandable support member 12. Each of the first,second, and third arch members 208′, 208″, and 208′″ can be made of aresiliently bendable material, such as a shape memory material. Thefirst, second, and third arch members 208′, 208″, and 208′″ can bespaced apart by sixth, seventh, and eighth distances D6, D7, and D8 thatare about equal to the third, fourth, an fifth distances D3, D4, and D5(respectively).

It will be appreciated that the apparatus 10 _(b) can additionally oroptionally include at least one secondary flexible arch member 210 forcontacting a non-commissural portion 212 (e.g., a frame or annulusportion) of the indwelling bioprosthetic valve 200. The secondaryflexible arch member 210 can have any configuration (e.g., shape andsize) to facilitate anchoring of the apparatus 10 _(b) in the indwellingbioprosthetic valve 200 and thereby prevent or mitigate migration of theapparatus once implanted. As shown in FIGS. 36A-B, for example, at leastone flexible secondary arch member 210 can have a U-shaped configurationand be in the form of a wire comprising a resiliently bendable material(e.g., a shape memory material). The at least one flexible secondaryarch member 210 can be made of the same or different material (ormaterials) as the expandable support member 12.

The at least one flexible secondary arch member 210 can have oppositelydisposed first and second end portions 214 and 216. When the apparatus10 _(b) is in the radially collapsed configuration (not shown), thefirst and second end portions 214 and 216 can be substantially flushwith the outer circumferential surface 56 _(b) of the expandable supportmember 12. When the apparatus 10 _(b) is in the radially expandedconfiguration, the first end portion 214 of the flexible secondary archmember 210 can protrude, extend, or be offset from (e.g., substantiallyradial to) the outer circumferential surface 56 _(b) (e.g., by about 1°to about 90° or more). As shown in FIGS. 36A-B, for example, the firstend portion 214 of the at least one flexible secondary arch member 210can engage a non-commissural portion 212 (e.g., the frame or annulus) ofthe indwelling bioprosthetic valve 200 when the apparatus 10 _(b) is inthe radially expanded configuration.

Depending upon the desired configuration of the apparatus 10 _(b), theat least one secondary flexible arch member 210 can have a length(defined by the distance between the first and second end portions 214and 216) about equal to the distance between the second end portion 50_(b) of the expandable support member 12 and the circumferential axisCA. One skilled in the art will appreciate that the length of the atleast one secondary flexible arch member 210 can be greater or less,however, depending upon the desired configuration of the apparatus 10_(b).

The second end portion 216 of the at least one secondary flexible archmember 210 can be integrally formed with the second end portion 50 _(b)of the expandable support member 12. For example, the at least onesecondary flexible arch member 210 can be a fluid extension of thematerial used to form the expandable support member 12. Alternatively,the second end portion 216 of the at least one secondary flexible archmember 210 can be attached to a desired point (or points) at the secondend portion 50 _(b) of the expandable support member 12 by any suitablemeans known in the art, such as soldering, an adhesive, etc. As shown inFIGS. 36A-B, the at least one secondary flexible arch member 210 can belocated between the flexible arch members 208 and securely affixed tothe second end portion 50 _(b) at first and second points on differentexpandable regions 62 _(b) of the expandable support member 12.

In one example of the present invention, the apparatus 10 _(b) shown inFIGS. 36A-B can be used to replace an indwelling bioprosthetic valve 200having first, second, and third commissural portions 206′, 206″, and206′″ (e.g., posts) spaced apart by third, fourth, and fifth distancesD3, D4 and D5. As described above, each of the first, second, and thirdarch flexible members 208′, 208″, and 208′″ of the apparatus 10 _(b) canhave a U-shaped configuration and be connected to alternating expandableregions 62 _(b) at the second end portion 50 _(b) of the expandablesupport member 12. Additionally, the apparatus 10 _(b) can includefirst, second, and third secondary flexible arch members 210′, 210″, and210′″ located at the second end portion 50 _(b) of the expandablesupport member 12 in between the first, second, and third flexible archmembers 208′, 208″, and 208′″.

The main body portion 52 _(b) of the apparatus 10 _(b) can include aplurality of wing members 60 spaced apart from one another by theexpandable region 62 _(b). As described above, each of the wing members60 can have an arch-like shape and include a first end portion 64, asecond end portion 66, and a flexible middle portion 68 extendingbetween the first and second end portions. As also described above, thefirst end portion 64 of each of the wing members 60 can be substantiallyflush with the outer circumferential surface 56 _(b) when the apparatus10 _(b) is in the radially collapsed configuration, and substantiallyradial to the outer circumferential surface when the apparatus is in theradially expanded configuration. The main body portion 52 _(b) caninclude any number, size, and configuration of wing members 60, asillustrated in FIGS. 1A-B and FIGS. 3A-8.

The main body portion 52 _(b) of the expandable support member 12 canadditionally or optionally include at least one expandable ring 218securely disposed about the outer circumferential surface 56 _(b). Oneskilled in the art will appreciate that the at least one expandable ring218 can additionally or optionally be included as part of the apparatus10 and 10 _(b) disclosed herein. The diameter of the at least oneexpandable ring 218 is adjustable and, as described below, can beadjusted to a predetermined diameter using a locking mechanism 230 (FIG.38). For example, the at least one expandable ring 218 (FIG. 34A) canexpand along with the expandable support member 12 and lock into thepredetermined diameter (via the locking mechanism 230) when the outercircumferential surface 56 _(b) of the expandable support member engagesa portion of the indwelling bioprosthetic valve 200 (e.g., the annulusor frame 204). By dynamically adjusting its diameter to the diameter ofthe expandable support member 12, the at least one expandable ring 218can provide additional strength and radial force to the main bodyportion 52 _(b) of the apparatus 10 _(b), prevent or mitigate recoil ofthe apparatus, and prevent or mitigate unwanted changes in the shape ofthe apparatus once implanted.

One or more expandable rings 218 can be disposed about the outercircumferential surface 56 _(b) near or on the circumferential axis CAand/or near or on the first end portion 48 and/or second end portion 50_(b) of the expandable support member 12. As shown in FIG. 37A, forexample, a first expandable ring 218′ can be disposed about the outercircumferential surface 56 near or on the circumferential axis CA.Alternatively, first and second expandable rings 218′ and 218″ can besecurely disposed about the first and second end portions 48 and 50 ofthe expandable support member 12 (FIG. 37B). The at least one expandablering 218 can be made of any one or combination of materials that allowsthe at least one expandable ring to dynamically adjust its diameterin-step the diameter of the expandable support member 12. The at leastone expandable ring 218 can be a continuous piece of material (e.g., acontinuously coiled wire) or, alternatively, a non-continuous piece ofmaterial comprising proximal and distal end portions (not shown). Itwill be appreciated that all or only a portion of the expandable ring218 can be covered with a biocompatible material, such as ePTFE.

In one example of the present invention, the at least one expandablering 218 can be spring-loaded to permit the at least one expandable ringto dynamically adjust its diameter in-step the diameter of theexpandable support member 12. As shown in FIG. 38, for example, the atleast one expandable ring 218 can include a spring 232 that isintegrally formed therewith. The spring 232 can allow the at least oneexpandable ring 218 to dynamically adjust its diameter in-step thediameter of the expandable support member 12. As also shown in FIG. 38,the locking mechanism 230 can comprise a tensioning member 234 (e.g., awire) having first and second ends 236 and 238. The first end 236 can besecurely attached to the at least one expandable ring 218 at a desiredpoint, such as at or near the spring 232. The second end 238 can includea slidable locking member 240 having a plurality of teeth 242 and a head244 to facilitate locking and adjustment of the at least one expandablering 218. It will be appreciated that the at least one expandable ring218 can include one more locking mechanisms 230.

As noted above, the expandable support member 12 can include abioprosthetic valve 202 secured within the main body portion 52 _(b). Inone example of the present invention, the bioprosthetic valve 202 cancomprise a stentless, substantially dehydrated valve. The substantiallydehydrated bioprosthetic valve can be treated and preserved with a drytissue valve procedure, such as the one described in U.S. Pat. No.6,534,004. Additionally, the substantially dehydrated bioprostheticvalve can be made with one or more pieces of tissue (e.g., pericardialtissue) as described above.

FIG. 39 illustrates another aspect of the present invention comprising amethod 220 for replacing a previously-implanted or indwellingbioprosthetic valve 200 having at least two commissural portions 206(e.g., posts) spaced apart by a first distance D1. As noted above,replacement of diseased bioprosthetic valves reduces the morbidity andmortality associated with native valvular disease, but comes at theexpense of risking complications unique to the implanted bioprostheticdevice. When bioprosthetic valves fail, for example, their removal andreplacement can entail a highly complicated and invasive procedure.Advantageously, the method 220 of the present invention can be used toreplace a previously-implanted or indwelling bioprosthetic valve 200that has failed without the need for invasive removal of the failed,which thereby avoids potential surgical complications and hardship onthe patient.

Although the method 220 is illustrated using a percutaneous approach toreplace an indwelling bioprosthetic mitral valve 200, it will beappreciated that other approaches (such as those listed above) can beused, and that the method can be used to replace other indwellingbioprosthetic valves, such as indwelling bioprosthetic tricuspid andaortic valves. Additionally, it will be appreciated that the method 220can alternatively be performed in a similar manner as the method 78 _(a)illustrated in FIGS. 26-32, i.e., employing a self-expandable apparatus10.

Referring again to FIG. 39, one step of the method 220 can includeproviding an apparatus 10 _(b) comprising an expandable support member12 and a bioprosthetic valve 202 secured therein (Step 222). Theexpandable support member 12 of the apparatus 10 _(b) can generallyinclude a first end portion 48, a second end portion 50 _(b), a mainbody portion 52 _(b) extending between the first and second endportions, an outer circumferential surface 56 _(b), and a plurality ofwing members 60′ and 60″ spaced apart from one another by an expandableregion 62 _(b). The main body portion 52 _(b) can additionally oroptionally include at least one expandable ring 218 securely disposedabout the outer circumferential surface 56 _(b). The second end portion50 _(b) can include at least two flexible arch members 208 spaced apartby a second distance D2 that is about equal to the first distance D1 ofthe indwelling bioprosthetic valve 200. In one example of the method,the apparatus 10 _(b) can be constructed as shown in FIGS. 34A-35B anddescribed above.

Prior to implantation of the apparatus 10 _(b), the dimensions of theindwelling bioprosthetic valve 200 can be determined (if not alreadydone so) using one or a combination of known imaging techniques, such asMRI, fluoroscopy, echocardiography, CT, angiography, and/or ultrasound.To enable delivery and deployment of the apparatus 10 _(b), theapparatus can then be loaded into a delivery catheter 92 at Step 224.For example, the apparatus 10 _(b) can be positioned about an inflatablemember 90 (e.g., a balloon) in the radially collapsed configuration(FIG. 40) and then loaded into the delivery catheter 92 in a knownmanner.

At Step 226, the apparatus 10 _(b) can be advanced through the deliverycatheter 92 to the indwelling bioprosthetic valve 200. The apparatus 10_(b) can be advanced to the indwelling bioprosthetic valve 200 in amanner similar or identical to the approach illustrated in FIGS. 20-22and described above. Briefly, for example, a guidewire 94 can beinserted into the vasculature via a femoral or jugular vein and, underimage guidance, steered through the vasculature into the inferior venacava 36 or superior vena cava 34 (respectively). The guidewire 94 canthen be passed across the right atrium 24 so that the distal end 96 ofthe guidewire pierces the interatrial septum 32. The guidewire 94 can beextended across the left atrium 26 and downward through the indwellingbioprosthetic valve 200 so that the distal end 96 of the guidewire issecurely positioned in the left ventricle 30. After the guidewire 94 isappropriately positioned, the delivery catheter 92 can be passed overthe guidewire and the apparatus 10 _(b) loaded thereon. An axial forcecan then be applied so that the apparatus 10 _(b) is passed over theguidewire 94 and positioned at the distal end 98 of the deliverycatheter 92.

Upon reaching the distal end 98 of the delivery catheter 92, theapparatus 10 _(b) can be deployed at Step 228. As shown in FIGS. 40-41,the apparatus 10 _(b) can be positioned adjacent the indwellingbioprosthetic valve 200 and then advanced therein. After positioning theapparatus 10 _(b) in the indwelling bioprosthetic valve 200, thedelivery catheter 92 can be progressively withdrawn to free theapparatus from the delivery catheter. If desired, the position of theapparatus 10 _(b) in the indwelling bioprosthetic valve 200 can bemonitored, controlled, and/or quality assured by one or more knownimaging techniques.

After positioning the apparatus 10 _(b) as shown in FIG. 41, theinflatable member 90 can be inflated using a suitable inflation medium,such as air or a saline solution. Inflation of the inflatable member 90can push the main body portion 52 _(b) of the expandable support member12 radially outward and thereby increase the diameter of the expandablesupport member. As the main body portion 52 _(b) expands, the expandablering 218 (or rings) can dynamically expand into contact with the frame204 (or annulus, depending upon the location of the ring or rings) ofthe indwelling bioprosthetic valve 200. Expansion of the main bodyportion 52 _(b) can simultaneously cause the wing members 60′ and 60″and the arch members 208 to radially expand. As shown in FIG. 42, forexample, the first end portion 64 of each of the wing members 60′ and60″ can move radially outward from the outer circumferential surface 56_(b) into contact with the leaflets of the indwelling bioprostheticvalve 200 to pin the leaflets against the frame 204 of the indwellingbioprosthetic valve. Additionally, each of the arch members 208 can moveradially outward into contact with the commissural portions 206 (e.g.,posts) of the indwelling bioprosthetic valve 200. For example, each ofthe arch members 208 can loop around or over each of the commissuralportions 206 (e.g., like a lasso).

With the apparatus 10 _(b) in the radially expanded configuration, thefirst and second plurality of wing members 60′ and 60″, the expandablering(s) 218, and the arch members 208 can secure the apparatus in placeof the indwelling bioprosthetic valve 200. Consequently, blood can nowflow through the bioprosthetic valve 202 of the apparatus 10 _(b). Asblood contacts the bioprosthetic valve 202, the interstices of thebioprosthetic valve can be re-hydrated and cause the bioprosthetic valveto obtain its original (or substantially original) properties and assumenormal (or substantially normal) blood flow performance. It should beappreciated that the bioprosthetic valve 202 may not be re-hydrated withblood where the bioprosthetic valve comprises a standard (i.e.,non-dehydrated) bioprosthetic valve (e.g., made of porcine tissue). Withthe apparatus 10 _(b) fully deployed, the inflatable member 90 can bedeflated, moved out of the mitral valve annulus 54, and the procedurecompleted.

It will be appreciated that other configurations of the “valve-in-valve”apparatus 10 _(b) and method 220 can be used to replace other types ofindwelling medical devices, such a previously-implanted or indwellingannuloplasty ring (not shown). For example, the apparatus 10 shown inFIGS. 1A-B can be securely disposed within an annuloplasty ring (notshown) to form an apparatus for replacing failed annuloplasty ring.Using one or a combination of the surgical implantation techniquesdiscussed above, such a “valve-in-ring” apparatus can implanted in placeof the failed annuloplasty ring to mitigate or prevent regurgitation ofblood therethrough.

Another aspect of the present invention is illustrated in FIGS. 43-45.The apparatus 10 _(c), is identically constructed as the apparatus 10and 10 _(b) shown in FIGS. 1A-B and 33A-36B, except where as describedbelow. In FIGS. 43-45, structures that are identical as structures inFIGS. 1A-B and 33A-36B use the same reference numbers, whereasstructures that are similar but not identical carry the suffix “c”.

Placement of bioprosthetic valves within previously-implanted orindwelling bioprosthetic valves can be difficult or impossible incertain subsets of patients due to the small diameter of such indwellingvalves. One such patient subset can include elderly patients, such asthose over 80 years of age. In these elderly patients, the annulus of anindwelling bioprosthetic valve can become too constricted over time andthereby prevent “valve-in-valve” or “stent-in-stent” replacementprocedures. Additionally, in pediatric patients, the reduced size of thevalve annuluses can prevent such “valve-in-valve” or “stent-in-stent”replacement procedures. Advantageously, the apparatus 10 _(c) of thepresent invention has a unique configuration to allow for replacement offailed indwelling bioprosthetic valves (or other devices, such asannuloplasty rings) in elderly and pediatric patients.

As shown in FIG. 43, the apparatus 10 _(c), can comprise an expandablesupport member 12 _(c), having a first end portion 48 _(c), a second endportion 50, a main body portion 52 extending between the first andsecond end portions, and a prosthetic valve 14 (such as a bioprostheticvalve 202). The apparatus 10 _(c), can be used to replace a failedbioprosthetic valve 200 that was previously implanted in the mitralvalve 18 (FIG. 43), the tricuspid valve 20 (not shown implanted), or theaortic valve 250 (FIGS. 44-45). The expandable support member 12 _(c),can be cork-shaped such that the first end portion 48, has a flaredconfiguration and the diameter of the first end portion is greater thanthe diameter of the second end portion 50. The expandable support member12 _(c), can have a 3D, saddle-shaped configuration and be made of oneor a combination of expandable materials (described above). Although notshown in detail, the main body portion 52 of the expandable supportmember 12 _(c), can also include a plurality of wing members 60 (asdescribed above).

The apparatus 10 _(c), can be implanted in the indwelling bioprostheticvalve 200 using a similar percutaneous technique as described in themethod 220 above. It will be appreciated, however, that one orcombination of the other surgical implantation techniques discussedabove may also be used to implant the apparatus 10 _(c). As shown inFIG. 43, the apparatus 10 _(c), can be implanted in an indwellingbioprosthetic valve 200 (e.g., mitral valve 18) such that the second endportion 50 and/or the main body portion 52 are securely seated in thebioprosthetic valve, and the first end portion 48 _(c), extends into theleft ventricle 30. Advantageously, the cork-shaped configuration of theexpandable support member 12 _(c) allows the apparatus 10 _(c) to fitwithin the narrowed cross-section of the indwelling bioprosthetic valve200 and thereby mitigate or prevent regurgitation of blood flowtherethrough.

Similarly, the apparatus 10 _(c), can be implanted in a failedindwelling bioprosthetic valve (e.g., aortic valve 250) as shown in FIG.45. Using a percutaneous approach, for example, the apparatus 10 _(c),can be implanted within the indwelling bioprosthetic valve 200 such thatthe second end portion 50 and/or the main body portion 52 are securelyseated in the bioprosthetic valve, and the first end portion 48 _(c),extends into the aorta 252.

It will be appreciated that the apparatus 10 _(c), can additionally oroptionally be constructed in a similar fashion as the apparatus 10 _(b)shown in FIGS. 33A-36B. Referring to FIGS. 45-46, for example, theapparatus 10 _(c), can comprise an expandable support member 12 _(c),having a first end portion 48 _(c), a second end portion 50 _(b), a mainbody portion 52 _(b) extending between the first and second endportions, and a prosthetic valve 14 (such as a bioprosthetic valve 202).As described above, the expandable support member 12 _(c), can becork-shaped such that the first end portion 48 _(c), has a flaredconfiguration and the diameter of the first end portion is greater thanthe diameter of the second end portion 50 _(b). The main body portion 52_(b) can include a plurality of wing members 60 (not shown in detail),and the second end portion 50 _(b) can include at least one flexiblearch member 208. Additionally or optionally, the second end portion 50_(b) can include at least one secondary flexible arch member 210 (notshown in detail) and/or at least one expandable ring 218.

The apparatus 10 _(c), can be implanted in the indwelling bioprostheticvalve 200 using a percutaneous technique, as described in the method 220above. As shown in FIG. 44, for example, the apparatus 10 _(c), can beimplanted in an indwelling bioprosthetic valve 200 (e.g., mitral valve18) such that the second end portion 50 _(b) and/or the main bodyportion 52 _(b) are securely seated within the bioprosthetic valve, andthe first end portion 48, extends into the left atrium 26. As describedabove, the at least one flexible arch member 208 can secure theapparatus 10 _(c) in the indwelling bioprosthetic valve 200 by engagingat least one commissural portion 206 (e.g., a post) of the indwellingbioprosthetic valve.

Similarly, the apparatus 10 _(c) can be implanted in a failed indwellingbioprosthetic valve (e.g., aortic valve 250) as shown in FIG. 45. Usinga percutaneous approach, for example, the apparatus 10 _(c) can beimplanted within the indwelling bioprosthetic valve 200 such that thesecond end portion 50 _(b) and/or the main body portion 52 _(b) aresecurely seated in the bioprosthetic valve, and the first end portion 48_(c) extends into the aorta 252.

From the above description of the invention, those skilled in the artwill perceive improvements, changes and modifications. For example, thesubstantially dehydrated bioprosthetic valve 14 and 202 may be exposedto a re-hydrating or rinsing solution while the apparatus 10, 10 _(b),and 10 _(c), is disposed within the delivery catheter 92 prior todelivery. Alternatively, the substantially dehydrated bioprostheticvalve 14 and 202 may by re-hydrated by blood while the apparatus 10, 10_(b), and 10 _(c) is being deployed in the vasculature. Additionally, itwill be appreciated that the apparatus 10, 10 _(b), and 10 _(c) canalternatively be configured as shown in FIGS. 46-48. Such improvements,changes, and modifications are within the skill of the art and areintended to be covered by the appended claims.

Having described the invention, we claim:
 1. A method for replacing adiseased cardiac valve, said method comprising the steps of: providingan apparatus comprised of a prosthetic valve secured within a main bodyportion of an expandable support member having a first end portion and asecond end portion, the main body portion including an outercircumferential surface, a circumferential axis extending about thecircumferential surface, and a first and second plurality of wingmembers each integrally formed with the main body portion of theexpandable support member and spaced apart from one another along thelength of the circumferential axis of the main body portion, wherein thesecond plurality of wing members is circumferentially spaced around anupper portion of the expandable support member and wherein the secondend portion of the expandable support member is comprised of at leasttwo flexible arch members; maintaining the expandable support member ina radially collapsed configuration; loading the apparatus into adelivery catheter; advancing the delivery catheter to the diseasedcardiac valve; and deploying the apparatus to a radially expandedconfiguration by extending both the first and second plurality wingmembers substantially radial to, and within the length of the axis ofthe outer circumferential surface of the main body portion, causing thefirst and second plurality of wing members to engage opposite sides ofan annulus of the diseased native cardiac valve to secure the apparatusin place of the diseased cardiac valve; and moving the at least twoflexible arch members from a collapsed configuration to an expandedconfiguration to offset the at least two flexible arch members from theouter circumferential surface of the main body portion by about 90°. 2.The method of claim 1, wherein said step of advancing the deliverycatheter to the diseased cardiac valve further comprises the step ofpositioning the delivery catheter so that the apparatus is adjacent thevalve annulus.
 3. The method of claim 1, wherein said step of providingan apparatus further comprises providing a substantially dehydratedbioprosthetic valve.
 4. The method of claim 3, wherein blood re-hydratesthe substantially dehydrated bioprosthetic valve before the apparatus isdeployed.
 5. The method of claim 3, wherein blood re-hydrates thesubstantially dehydrated bioprosthetic valve after the apparatus isdeployed.